The field of the present invention relates to fluid storage tanks.
Portable fluid storage tanks may be useful in a variety of circumstances. Portable relay tanks are often used for fire-fighting, particularly in rural or wilderness areas. Relay tanks are typically available that include a rigid frame with a liner. Alternatively, a relay tank may be provided as a frameless, free-standing tank (essentially a bag-like liner with a stiff or rigid ring around its top opening. Rigid-framed tanks are most suitable for assembly or deployment on substantially flat, substantially horizontal surfaces. They may not be suitable for use on rough, uneven, and/or sloped terrain. Free-standing frameless tanks may be deployed on such terrain, but may be difficult to fill and may become mechanically unstable (i.e., they sometimes may tend to roll over, spilling the fluid contents).